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Peering into a binocular microscope in a busy laboratory, Brad Richbourg focuses the slide and describes what he sees: a human hair with its tiny, fleshy root intact and tiny dots of pigment along the shaft.
The lab instructor walks over to take a look.
"There it is--it's got tissue on the end, probably hurt when it was yanked out--you could do a full DNA profile on that," he says. "And remember: the more pigment dots, the darker the hair."
It sounds like an episode from CSI: Crime Scene Investigation, but it's just another weekly lab exercise for the 108 students enrolled in Forensic Chemistry 107. USC has offered advanced forensics chemistry for 10 years--in fact, long before CSI and other TV shows of that ilk became popular--but this course is new and intended for non-science majors. It appeals to criminal justice majors and anyone else intrigued with the details of crime scene analysis.
"A lot of CSI is not good science--it's entertaining but fictional. In this course the students learn from professionals who are actually doing forensics work every day," said William Brewer, '91 Ph.D., an adjunct professor in USC's Department of Chemistry and Biochemistry who helped organize the course.
Demi Garvin, '87 PharmD., with the Richland County Sheriff's Department, is one of those professionals. She bemoans the fact that CSI is creating unrealistic expectations for jury members and hopes that USC's course will give students--who be future jurors--a more accurate depiction of what forensics analysis can do.
From differentiating the shapes of carpet fibers to testing for gunpowder residue, Forensic Chemistry 107 is like an FBI lab primer. And most students can't get enough.
"I'm a pre-med major and really interested in pediatrics, but I've landed an internship this summer with the S.C. Law Enforcement Division's forensics lab," said Jilian McAlum, a junior from Hodges, S.C. "I want to see if I really like it enough to consider changing direction."
William Martin, a marine science junior from Columbia, likes learning about the science behind crime scene investigation. "The instructors say so much of CSI is fakey, but the concept is correct. Technology can reveal a lot of clues from a little bit of evidence."
Brad Richbourg is a senior criminal justice major whose academic advisor strongly encouraged him to take Forensic Chemistry 107. He likes the way the weekly laboratory sessions build on the lectures, most of which feature a guest speaker who cites actual criminal cases to illustrate the lecture topic.
On this particular evening, David Collins from the Richland County Sheriff's Department is discussing firearm and toolmark identification. He shows slides of the marks made by a knife and a screwdriver on an ATM door and describes the modified Griess test, which reveals the presence of nitrites from burning gunpowder.
The lecture hall is hushed as he recounts the case of a woman found in a retail business, shot dead at point blank range. The major evidence, .30 caliber bullet fragments, was confusing at first, he said.
"They didn't look like any of the .30 caliber bullets in our database," Collins said.
More ballistics tests revealed that the bullets had been shot in a different caliber rifle, which explained the odd markings. Based on that and other evidence, police questioned a nearby pawn shop employee who eventually confessed to the crime.
The highlight of the evening lecture comes when Gray Amick, '93 Ph.D., director of the DNA laboratory for the Richland County Sheriff's Department, fires a pistol loaded with blank ammunition. The lights are turned down, and students gasp as the .38 special roars and belches flame and smoke.
Amick's hands are wiped with a cloth that is chemically treated to reveal small, dark dots--evidence of gunpowder residue. The cloth is put in a bottle and passed from student to student while the lecture progresses.
"Keep in mind that gunpowder residue might also show up on the victim's palms," Brewer tells the class. "It's not uncommon for a person to raise their arms defensively before they're shot at close range."
With that stark fact etched in their brains, students dismiss from the lecture, ready to tackle next week's lab exercise. Only some of them will become forensic chemistry analysts, but all are learning what every convicted criminal already knows: with good science, even the tiniest bit of evidence can sometimes solve a crime.
4/06
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Students complete lab work for Forensic Chemistry 107.
